For any apparatus to be handled by a user, user interface is of high importance of how the apparatus will work in practice. This particularly apply to portable devices, where there is limited space for the user interface, and at the same time, it is desirable that the user interface is easily handled also when the user is moving or performing simultaneous tasks. An approach for simplified input interfaces is use of single-button input. An example of this is provided in U.S. Pat. No. 5,966,093 A, which discloses a switch monitor which determines when first, second and third status commands are issued based upon first, second and third predetermined sequential switch output states. A microprocessor in conjunction with a memory maintains timers for the status commands. However, this approach requires some rhythm sense from the user, and may be hard to learn to use. Therefore, there is a need for a simplified user input that is easier to learn how to use.